The present disclosure generally relates to gyratory rock crushing equipment. More specifically, the present disclosure relates to a system and method for hydraulically removing a socket from the main shaft of a cone crusher.
Rock crushing systems, such as those referred to as cone crushers, generally break apart rock, stones or other material in a crushing gap between a stationary element and a moving element. For example, a conical rock crusher is comprised of a head assembly including a crushing head that gyrates about a vertical axis within a stationary bowl positioned within the mainframe of the rock crusher. The crushing head is assembled surrounding an eccentric that rotates about a fixed main shaft to impart the gyrational motion of the crushing head which crushes rock, stone or other material in a crushing gap between the crushing head and the bowl. The eccentric can be driven by a variety of power drives, such as an attached gear, driven by a pinion and countershaft assembly, and a number of mechanical power sources, such as electrical motors or combustion engines.
The crushing head of large cone crushers is rotationally supported upon a stationary main shaft. The stationary main shaft includes a socket that is securely attached to the main shaft. The socket has a heavy interference fit with the main shaft which is necessary for the socket to stay assembled to the main shaft while crushing to prevent motion between these two components. Presently, when the cone crusher is disassembled for maintenance, the socket must be removed from the top end of the main shaft. Typically, during the removal process, the socket is heated, which causes the socket to thermally expand relative to the main shaft, which temporarily creates clearance between the two components in the fit area. Once the socket has been heated, jack screws are used to push the socket off the main shaft and an overhead crane is used to completely remove the socket from the main shaft.
Problems exist with the current method of heating the socket and utilizing jack screws to separate the socket from the main shaft. These problems include the relatively large amount of labor and time required to heat the socket and quickly utilize jack screws to move the socket relative to the main shaft. Specifically, if the socket is not removed quickly enough, the heat from the socket is transferred to the main shaft, which causes the main shaft to expand and the clearance between the socket and the main shaft necessary for disassembly using the jacking screws no longer exists. When this happens, the main shaft and socket must be allowed to cool and the process is repeated. Further, during this removal process, the socket can drag along the main shaft, which causes the contact surface to become scored, thus decreasing the effective life of both the socket and the main shaft. The removal process described above requires experienced personnel and a significant amount of time to remove the socket without damaging either the socket or the main shaft.
Since the socket needs to be removed each time the eccentric is disassembled from the crusher, any improvement in the socket disassembly process would be useful in reducing the amount of time and experience needed during the maintenance process.